I am working on dimensioning. I seem to do fine when working with full rate but I fall short while doing our half rate stuff.
I have a Ericsson system, my test site has 2 TRX’s (16 FR-TS), 4 dedicated data (4 FR-TS), 1 BCCH(1 FR-TS ),1 Sdcch(1 FR-TS). This should leave me (20 HR-TS). So with the 20 HR-TS I should be able to handle 13.1 to 13.2 erlangs of traffic.
In reality it does not work like that. I am showing blocking at as low as 2.8 Erlangs. Even if this was running only FR, I should be able to handle about 5.1 Erlangs of traffic. We have had it up to 5.2 Erlangs with no blocking.
For starters is my calculations above correct? Also does anyone have any suggestions on how I can get the use of the HR-TS, or why I might be blocking with such low usage.